* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: "PingFang SC", "Microsoft YaHei", sans-serif;
}

body {
    background-color: #f5f8ff;
    color: #333;
    background-repeat: no-repeat;
    background-size: cover;
    background-position: center;
    min-height: 100vh;
}

/* Header styles */
header {
    background-color: white;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
    padding: 0.8rem 2rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.logo {
    color: #3454d1;
    font-size: 1.2rem;
    font-weight: bold;
}

.nav-menu {
    display: flex;
    gap: 2rem;
    list-style: none;
}

.nav-menu a {
    text-decoration: none;
    color: #666;
    padding: 0.5rem 0;
    position: relative;
}

.nav-menu a:hover {
    color: #3454d1;
}

.nav-menu a.active {
    color: #3454d1;
    font-weight: 500;
}

.nav-menu a.active::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    width: 100%;
    height: 2px;
    background-color: #3454d1;
}

.user-actions {
    display: flex;
    gap: 1rem;
}

.user-actions button {
    padding: 0.5rem 1.5rem;
    border-radius: 4px;
    border: none;
    cursor: pointer;
}

.user-actions button.primary {
    background-color: #3454d1;
    color: white;
}

.user-actions button:not(.primary) {
    background-color: white;
    color: #3454d1;
    border: 1px solid #3454d1;
}

/* Hero section */
.hero {
    background-color: white;
    padding: 4rem 2rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.hero-content {
    flex: 1;
    padding-right: 60px;
}

.hero-title {
    font-size: 36px;
    font-weight: bold;
    margin-bottom: 20px;
}

.hero-description {
    color: #666;
    font-size: 16px;
    line-height: 1.6;
    margin-bottom: 30px;
}

.hero-buttons {
    display: flex;
}

.hero-buttons button {
    padding: 10px 25px;
    margin-right: 15px;
    border-radius: 5px;
    font-size: 14px;
    cursor: pointer;
}

.hero-buttons button.primary {
    background: #2857f3;
    color: #fff;
    border: none;
}

.hero-buttons button.secondary {
    background: transparent;
    border: 1px solid #2857f3;
    color: #2857f3;
}

.hero-image {
    flex: 1;
    display: flex;
    justify-content: center;
}

.hero-image img {
    max-width: 100%;
    height: auto;
}

/* Features section */
.features {
    background-color: #f8faff;
    padding: 2rem 2rem;
    text-align: center;
}

.section-title {
    font-size: 1.8rem;
    font-weight: bold;
    margin-bottom: 0.5rem;
}

.section-subtitle {
    color: #666;
    font-size: 1rem;
    margin-bottom: 1.5rem;
}

.feature-cards {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1.5rem;
    max-width: 1200px;
    margin: 0 auto;
}

.feature-card {
    background: white;
    padding: 1.5rem;
    border-radius: 8px;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.05);
}

.feature-icon {
    font-size: 2rem;
    margin-bottom: 0.8rem;
}

.feature-icon i {
    font-size: 24px;
    color: #2857f3;
}

.feature-title {
    font-size: 1.2rem;
    font-weight: bold;
    margin-bottom: 0.5rem;
}

.feature-description {
    font-size: 0.9rem;
    line-height: 1.5;
    color: #666;
}

/* Evaluation dimensions */
.evaluation {
    background-color: white;
    padding: 4rem 2rem;
    text-align: center;
}

.dimension-cards {
    display: flex;
    justify-content: space-between;
    flex-wrap: wrap;
}

.dimension-card {
    width: 23%;
    background: #f9f9f9;
    padding: 20px;
    margin-bottom: 20px;
    border-radius: 5px;
    text-align: center;
}

.dimension-image {
    height: 100px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 15px;
}

.dimension-image img {
    max-width: 80%;
    max-height: 80px;
}

.dimension-title {
    font-size: 16px;
    font-weight: bold;
    margin-bottom: 10px;
}

.dimension-description {
    color: #666;
    font-size: 14px;
}

/* Data analysis */
.data-analysis {
    background-color: #f8faff;
    padding: 4rem 2rem;
    text-align: center;
}

.charts {
    display: flex;
    justify-content: space-between;
    margin-top: 40px;
}

.chart {
    width: 48%;
    border-radius: 5px;
    padding: 20px;
    border: 1px solid #eee;
}

.chart-title {
    font-size: 18px;
    font-weight: normal;
    margin-bottom: 30px;
    text-align: center;
}

.chart img {
    max-width: 100%;
    height: auto;
}

/* How to use */
.usage {
    background-color: white;
    padding: 4rem 2rem;
    text-align: center;
}

.step-cards {
    display: flex;
    justify-content: space-between;
    margin-top: 40px;
}

.step-card {
    width: 30%;
    display: flex;
    flex-direction: column;
    align-items: center;
}

.step-icon {
    width: 80px;
    height: 80px;
    background-color: #f0f3ff;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 20px;
}

.step-icon i {
    font-size: 24px;
    color: #2857f3;
}

.step-title {
    font-size: 16px;
    font-weight: bold;
    margin-bottom: 10px;
}

.step-description {
    color: #666;
    font-size: 14px;
    line-height: 1.6;
}

/* Footer */
footer {
    background-color: #2c3e50;
    color: white;
    padding: 4rem 2rem 2rem;
    margin-top: 2rem;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    margin-bottom: 40px;
}

.footer-column {
    flex: 1;
    padding-right: 20px;
}

.footer-title {
    font-size: 18px;
    font-weight: bold;
    margin-bottom: 20px;
    color: #fff;
}

.footer-description {
    color: #bbb;
    font-size: 14px;
    line-height: 1.6;
    margin-bottom: 20px;
}

.footer-links {
    list-style: none;
}

.footer-links li {
    margin-bottom: 10px;
}

.footer-links li a {
    color: #bbb;
    text-decoration: none;
    font-size: 14px;
}

.footer-bottom {
    padding-top: 20px;
    border-top: 1px solid #333;
    display: flex;
    justify-content: space-between;
    color: #999;
    font-size: 14px;
}

.social-icons {
    display: flex;
}

.social-icons a {
    margin-left: 15px;
    color: #fff;
}

/* Responsive design */
@media (max-width: 992px) {
    .hero {
        flex-direction: column;
        padding: 40px 5%;
    }

    .hero-content {
        padding-right: 0;
        margin-bottom: 30px;
        text-align: center;
    }

    .hero-buttons {
        justify-content: center;
    }

    .feature-cards {
        flex-direction: column;
    }

    .feature-card {
        margin-bottom: 30px;
    }

    .dimension-card {
        width: 48%;
    }

    .charts {
        flex-direction: column;
    }

    .chart {
        width: 100%;
        margin-bottom: 20px;
    }

    .step-cards {
        flex-direction: column;
        align-items: center;
    }

    .step-card {
        width: 80%;
        margin-bottom: 30px;
    }

    .footer-content {
        flex-direction: column;
    }

    .footer-column {
        margin-bottom: 30px;
    }
}

@media (max-width: 768px) {
    header {
        flex-direction: column;
    }

    .logo {
        margin-bottom: 20px;
    }

    .nav-menu {
        margin-bottom: 20px;
        flex-wrap: wrap;
        justify-content: center;
    }

    .nav-menu li {
        margin: 5px;
    }

    .dimension-card {
        width: 100%;
    }

    .footer-bottom {
        flex-direction: column;
        align-items: center;
    }

    .footer-bottom p {
        margin-bottom: 15px;
    }
}

/* Animations and transitions */
.hero-buttons button,
.nav-menu li a,
.user-actions button,
.footer-links li a {
    transition: all 0.3s ease;
}

.hero-buttons button:hover,
.user-actions button:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1);
}

.nav-menu li a:hover,
.footer-links li a:hover {
    color: #2857f3;
}

.dimension-card:hover,
.feature-card:hover {
    transform: translateY(-5px);
    transition: transform 0.3s ease;
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.05);
}

/* 为每个section添加微妙的分隔线 */
section {
    border-bottom: 1px solid rgba(0, 0, 0, 0.05);
}